Exhaust hood for oxygen furnaces



June 23, 1964 H, McFEATERs 3,138,648

EXHAUST HOOD FOR OXYGEN FURNACES Filed NOV. 19, 1958 7 Sheets-Sheet l i ZI'G. I

June 23, 1964 H. L. MCFEATERS 3,138,648

EXHAUST HOOD FOR OXYGEN FURNACES Filed Nov. 19, 1958 '7 Sheets-Sheet 2 11/3 ATmRNEYS.

June 23, 1964 H. L. MCFEATERS EXHAUST HOOD FOR OXYGEN FURNACES 7 Sheets-Sheet 3 Filed Nov. 19, 1958 IN V EN TOR. HARRY L. McFEA 7-525 BY.

June 23, 1964 MCFEATERS 3,138,648

EXHAUST HOOD FOR OXYGEN FURNACES Filed Nov. 19, 1958 7 Sheets-Sheet 5 June 23, 1964 H. L. MCFEATERS EXHAUST HOOD FOR OXYGEN FURNACES Filed Nov. 19, 1958 7 Sheets-Sheet 6 I #1026 I02: H

a a g w, m C 2 p m 2 m d wm INVENTOR MCFEA TERS 6 HARRYL.

HIS A TTORNEYS.

June 23, 1964 H. L. MCFEATERS EXHAUST HOOD FOR OXYGEN FURNACES Filed Nov. 19, 1958 7 Sheets-Sheet '7 J G. 18 B/fbE/SYL McFeATE/es INVENTOR.

H/SATT'ORNEVS- United States Patent 3,138,648 EXHAUST HOGD FOR OXYGEN FURNACES Harry L. McFeater's, New Castle, Pa, assignor to Pennsylvania Engineering Corporation, New Castle, Pa., a corporation of Pennsylvania Filed Nov. 19, 195-8, Ser. No. 775,076 13 Claims. (Cl. 266-35) This invention relates to improved apparatus for refining metal by a so-called oxygen process, and particularly, to exhaust hood apparatus for use with a furnace or converter vessel and associated apparatus employed in making or refining a metal, such as steel, by an oxygen blow process.

This is a continuation in part of my application No. 722,257, filed March 18, 1958, entitled Hood Post Crane, now US. Patent 3,026,102.

A conventional oxygen-blow process involves the utilization of a lance for introducing the oxygen gas into a refining vessel or furnace through its mouth and towards the surface of the metal contained therein. Such a process imparts relatively high temperatures (in the neighborhood from about 3,000 to 3,200 degrees F. or higher) to the fume or gas discharge from the furnace vessel (hot fluid eflluent generator). The fume or gas discharge which is incident to the blowing or refining of the metal involves a considerable amount of smoke, flame, and oxide fume, such as of carbon, sulfur, phosphorus, and of the metal such as iron. The handling of the effluent discharge or evolved fume has become an important factor in a process of this type, not only because of its high temperature, but because of its tendency to contaminate the surrounding atmosphere.

Recently, steps have been taken to condition the evolved gases, fume discharge or hot effluent and to recover more valuable portions thereof, such as the metal oxides. In this connection, I have developed so-called exhaust hoods for conducting the discharge from the vessel to receiving or collecting and cooling apparatus (effluent conditioning receiver) to condition the discharge and make it innocuous as to the atmosphere. In this connection, I have shown a so-called spark trap type of initial receiver which is not, itself, a part of the present invention, but which may be used with my hood construction.

Cost and other factors have led to the adoption of oxygen refining processes and as their use becomes more general, the demand has been for larger installations or for installations having greater capacities. Of course, with greater vessel' capacities, the volume of the fume or gas discharge becomes greater and, for a 25 ton converter, may involve a volume in the order of 156,000 cubic feet per minute.

Although it has been customary to line the converter vessel, itself, with a refractory lining to protect the metal shell and provide for replacement, I have determined that a refractory lining is not practical from the standpoint of an exhaust hood. However, this matter has been carefully evaluated and considered from the standpoint of my present construction, since I contemplate employing a gas-tight hood as an interfitting, gas-tight, direct adjunct with and to form a discharge mouth of the vessel, and in such a manner as to prevent the aspiration of atmospheric ambient or surrounding air into the hood. Such an aspiration normally tends to have some cooling effect on the discharge from the vessel, but greatly increases the volume of gases and, in such a manner, as to decrease the percentage content of the effluent to the whole. As a result, my hood construction must be capable of withstanding even higher temperatures than heretofore encountered in connection with an installation employing a spaced relationship between the hood and the vessel, with or without an intermediate, sectioned connecting collar.

, 3,138,548 Patented June 23, 1964 However, I have discovered that the receiving apparatus may have a lesser through-put capacity and can be operated on a more efiicient basis as to the recovery or re moval of fume materials.

At this point, it may be noted that I employ a new concept in a converter or exhaust hood installation in which the hood effectively becomes an extension part or adjunct of the vessel, as Well as a highly effective agency for collecting, directing or transmitting the evolved gases or fume to a receiving, collecting or treating apparatus, without substantial ambient air or atmospheric gas dilution. In this manner, I not only preclude any contamination of the melt or molten metal during the blow-refining operation thereof, and while the fume discharge continues, but also greatly minimize the volume of gas to be handled in the treating-collecting apparatus. This is highly important, particularly from the standpoint of the use of increased capacities of vessel apparatus. As a result, the discharge handled by my exhaust hood apparatus is essentially the discharge resulting from the introduction of the oxygen into the melt, including fume reactional products of the refining operation.

Returning to the problem associated with higher temperatures in the exhaust hood, a refractory lining will greatly increase the dead weight of a hood in connection with its handling, and thus tends to decrease the flexibility of its utilization. Also, the products of the exhaust fume have a tendency to chemically react and spoil the refractory material, thus entailing a relatively high consumption of refractory material per ton of steel. Spitting slag' and droplet skull tend to collect on the rough and porous face of a hood refractory wall and produce a heavy buildup, such that whole portions of the refractory lining break loose. Further, I have discovered that a refractory lining does not lend itself to water spray applications to the fume discharge, such as may be employed for further cooling the fume in the hood. To increase fume collecting efiiciency, it is desirable to spray water as close to the converter vessel as possible, in order to wet the fume particles at the time that they are at their minimum grain sizes. Such sizes tend to increase or grow as the distance of travel of the discharge increases from the vessel, with a minimum grain size occurring at the mouth of the vessel.

I have been able to eliminate superficial and inefiicient intermediate connecting collar means between the vessel mouth and the hood and to do so without the necessity of making the hood in outwardly-swinging hinged sections, in order to permit normal tilting operations of the vessel. I have determined that a hinged section connecting means for the vessel mouth is impractical, because of the fact that higher temperatures are there encountered that tend to warp and deform a non-continuous or sectioned connecting structure and to iamb the swing, hinge or pivotal connections of its sections; Also, a good fluidtight seal cannot be assured with such a construction.

In carrying out my invention, it is important not only to provide a good fluid-tight seal between the exhaust hood and the spark trap or other type of effiuent conditioner, but to also provide a fluid-tight seal between the mouth of the vessel or converter and the hood and of a type that can be accurately aligned and readily disconnected without sticking. I provide a gas-tight or leaf-proof construction which closes off the furnace vessel from the surrounding atmosphere, but at the same time, provides a conducting path such that the hot effluent escapes or is delivered in a direct, fully enclosed, smooth, cooling-wall path or passageway as it is generated. The mouth of the hood is continuously integral about the area that defines an effective sealing-off joint with the mouth of the vessel.

I have been able to employ a Water-jacketed metal wall type of hood construction for this purpose which may function to cool the eflluent in the neighborhood of a few hundred degrees (depending upon the internal surface area). It moves the gases quickly and efliciently along relatively cool passageway surfaces, such that adherence of condensate from the fume is minimized as to such surfaces. Further, provision has been made for introducing processing material through the hood, such as additive materials and oxygen, while maintaining an atmospheric scaled-off relationship. I employ and utilize an exhaust lance in an extending-through relationship with respect to one open wall portion of the hood and introduce additive materials through a second open wall portion, as by a suitable gravity, or mechanical feed means. The openings in the hood for the additive feed and the introduction of the lance are provided with water-jacketed closure gates of a nature, such that during the utilization of the hood, the open portions for introducing processing material (oxygen and additives) will have a substantially fluid-tight relationship.

In providing a practical wall construction for the hood and gate parts used therewith, I have discovered that internal welds should be avoided where convex corners or joints are provided and that the plate wall members, should be extended about 2 or 3 inches from a corner to a flat portion to provide a joint where a full Penetration weld is made. I weld end or edge portions on flat surfaces a few inches away from corners or bent portions. End or nose wall portions of the hood wall are of rounded contour and may be half section lengths of pipe or tubing which are welded back of the immediate edge or nose.

To support the inner and outer shell walls of the jacketed construction with respect to each other, I provide a somewhat flexible or expansion and contracting permitting arrangement, wherein bolts are secured to the cold or outer side wall and have an adjustably-set, permanent, indirectly-connected relationship with the hot side wall. There should be no solid weld connections between the inside and outside plate or wall members across the inner spacing between them. Fin or web baflling employed in the water-jacketed spacing between inner and outer side wall members are secured only to the outer or cold side member to extend towards the hot side member in a clearance spaced relationship with respect thereto. In this manner, the nose edges or end portions of the wall construction are reinforced and desired flow paths are provided without securing the hot side directly to the cross elements employed. Outward expansion and inward contraction are thus controlled or limited.

Also I employ removable, clamping-sealing, plug fittings in the outer or cold side wall or plate member which are sufficient in size for a hand removal of sludge in cleaning out the cooling fluid space or chamber. In sealing off the lance opening in the hood, I provide lance gates having gate fingers or closure elements that are pivotally opened and closed about the lance. I provide somewhat similar but unitary means for the additive opening.

The hood is provided with at least one upwardlyoutwardly-projecting shell wall portion or collar in its top wall to define an open wall portion for introducing processing material through the hood to the generator, converter or furnace vessel. I have shown an open wall portion for the oxygen lance as well as an open wall portion for delivering additives to the melt. Such top open portions are provided with seating lips, sealing face portions or rim flanges for cooperating with closure gate means that, like the hood, itself, are water-jacketed or cooled. Gate-like fingers are provided for the seating portion of the lance opening, while a single plate-like gate member is employed for the additive opening. Both gates are provided with means or mechanism for swinging them in a wiping relationship with their respective seats, into and out of passageway closing-ofl or sealing positions.

I have shown an additive funnel, chute or open feed wall secured to and positioned in alignment above the extension portion of the hood which defines the additive open wall portion, so that its lower edge or end also forms a seating or sealing lip portion for the closure gate means. I shOW the employment of an additive conductor conduit or conveyor tube having an adjustable universal type of joint with respect to a discharge nozzle or open-end plug carried thereby; the nozzle has a tapered seating face and is self-aligning, such that when moved or introduced into the seating surface of the additive feed wall or funnel, it will form a flexible, self-seating, fluid-seal.

An opening through one half portion of the additive gate means defines a seating and sealing annulus or ring when the gate is moved to its open portion, such that the ring seals off spacing between the feed wall or funnel and the open wall portion of the hood, when the opening through the half portion of the gate defines a feed passageway therethrough into the hood. Thus, even when the additive gate is opened and additive materials are being fed into the vessel, the feed system employed provides a fluid-sealed-oif relationship from the standpoint of the ambient atmosphere and its gases.

The hood is flexibly suspended from a suitable overhead structure of a nature such that it may be raised and lowered as a unit directly into and out of a self-aligning sealed relationship with the mouth of the vessel, as well as with the inlet end portion of the diluent receiver or spark trap apparatus. In addition, means is provided for swinging the hood as a unit out of alignment with the generator or furnace vessel, after it has been raised to an upper position, to facilitate access to the spark trap or receiving apparatus, pouring of the melt, and charging of the vessel. Prior to the raising of the hood, the lance gate means may be swung to an open position to free the lance and permit its removal from the hood, if desired. The initial opening of the gate means for the lance is not necessary, as it can be at least partially raised when the hood is raised. In any event, means is provided above an upper or lance jib to raise the lance to clear the mouth of the vessel when it is to be swung with the hood to one side or to raise it completely out of the hood when it is to be repaired or replaced. v

I have found it necessary to avoid one-piece metalweld-secured connecting elements, such as cross or stay rods, between the inner or hot shell wall and the outer or chill shell wall, as they will burn out and cause water leakage by burning out the inner plate member. In other words, there should not be any direct or efficient heattransfer securing means on the outer shell wall that is also secured (across the cooling fluid chamber) to the inner or hot shell wall, if damage to or burning out of the inner shell wall is to be avoided. I have found that heat will tend to concentrate in a direct transfer element of limited extent, such as a one-piece metal cross element secured to both shell walls. I have devised a cross element or bolt structure which meets this problem and, at the same time, provides a cross support that controls expan- Sion and contraction between the inner and outer members.

The accompanying drawings illustrate an embodiment of my invention wherein:

FIGURE 1 is a somewhat reduced side view in elevation showing a furnace vessel or converter installation employing apparatus constructed in accordance with my invention; in this figure, I have shown an exhaust hood in a hermetically sealed or fluid-tight relationship with respect to the vessel and an eflluent receiving apparatus, and with an oxygen blow lance in an operating position within the vessel;

FIGURE 1A is an enlarged fragmental section in elevation through an upper end or outlet mouth portion of the vessel or furnace A, and particularly illustrating seating or sealing means for cooperating with and forming a fluid sealed-elf joint with a downwardly-projecting inlet or nose portion of the hood;

FIGURE 2 is a top plan view on the scale of and of the installation of FIGURE 1 with closure gates for the hood omitted;

FIGURE 3 is an enlarged top plan view of the hood shown in FIGURES 1 and 2;

FIGURE 4 is a side sectional view in elevation taken along line IV-IV of and on the scale of FIGURE 3; this view also shows the position of closure gates and an open-end additive feed wall part or funnel in dot-anddash lines;

FIGURE 5 is a back end view in elevation on the scale of and taken along the line V-V of FIGURE 3, showing an outlet or delivery end of the hood construction;

FIGURE 6 is a fragmental top section through the hood of and on the scale of FIGURE 5 with an outside, chill shell or plate wall broken away and showing a partial development of stay bolts and bafiles that are secured to project from the inner side of the outside plate wall;

FIGURE 7 is an enlarged fragmental cross-section in elevation through a Wall portion of an eflluent inlet, lower end or nose portion of the hood construction and showing a removable, cleaning-out closure;

FIGURE 8 is a fragmental cross-section through plate members of the inner and outer walls of the hood on the scale of FIGURE 7, illustrating details of the mounting of baflies and stay bolts therebetween;

FIGURE 9 is an enlarged fragmental cross-section on the scale of FIGURES 7 and 8 through a wall portion of the inlet nose of the hood construction, illustrating details of the fabrication and construction of the wall as well as showing the mounting of a connector nipple thereon;

FIGURE 10 is a front perspective view in elevation of the hood of FIGURE 4, particularly illustrating the construction and mounting of a funnel, chute or open-end feed Wall, a feed nozzle plug for feeding material additions to the furnace through the hood, and gate means for opening and closing-off a feed collar, rim flange or upwardly-open wall portion of the hood; this view also shows a collar or flange defining a second upwardly-open wall portion in the hood for introducing an oxygen lance therethrough;

FIGURE 10A is a side sectional detail in elevation, on a reduced scale as to FIGURE 10, showing how a feed plug may be swung into and out of a sealed relation within the feed funnel;

FIGURE 11 is a top plan view on the scale of FIGURE 10, and particularly illustrating the construction and operation of gate means for opening and closing-off the the feed open portion in the hood and showing the aligned funnel or open-end feed wall which is associated therewith; the full-line position of the gate means of this figure illustrates a feeding position wherein an opening or passageway through the gate means is aligned with the feed opening in the hood; the dot-and-dash lines show the position of the gate means to close-off the feed open- FIGURE 12 is a fragmental section in elevation on the scale of FIGURES l0 and 11 and illustrating the positioning of the gate means with respect to the feed opening and the funnel or feed wall;

FIGURE 13 is a greatly enlarged section in elevation through a feed end portion of a conveyor or conduit shown in FIGURE 10; this figure particularly illustrates a universal type of connecting joint for the feed plug or nose;

FIGURE 14 is an enlarged horizontal view in partial section showing the mounting, construction and operation of a two-part gate or closure means for the lance opening in the hood construction;

FIGURE 15 is a side sectional view in elevation on a reduced scale with respect to FIGURE 14; this view shows gate means in a closed position while FIGURE 14 shows it in an open position;

FIGURE 16 is an end sectional View on an enlarged scale with respect to FIGURE 14; in this view the gate means is also shown in a closed position with respect to the lance;

FIGURE 17 is a top plan view of the mechanism of and on the scale of FIGURE 14 showing the gate means in a closed position with respect to the lance, and particularly illustrating cooling fluid supply lines, gland connections for providing a circulation of cooling fluid to the parts or members of the gate means, and also fluid supply and exhaust connections to a fluid-operated motor for opening or closing the gate means; and

FIGURE 18 is a front view in elevation and partial section on the scale of and taken along the line XVIII-XVIII of FIGURE 17.

Operating Installation Particular reference is made to FIGURES 1 and 2 which illustrate an operating layout for a single vessel or furnace installation for refining metal. In this layout, I have shown generator or converter vessel A in an upright position with the lip edges of its open mouth portion fully enclosed and hermetically sealed by an effluent inlet end, nose or mouth portion of an exhaust hood D. The hood D is shown as defining a closing-off passageway which extends substantially at right angles from the vertical direction of introduction of the effluent from the vessel A to deliver effluent gas or fume, directly in an angular path to a receiving or conditioning apparatus or spark trap G. The hood has a side outlet mouth or exhaust portion surmounted by a seating, side flange rim portion 16d (see also FIGURE 4) which is adapted to be positioned in a sealed-off relationship with respect to an inlet flange portion 35 of the receiving apparatus G.

In FIGURE 1, an oxygen blow lance E (employed to refine metal in the vessel A) is shown in a raised or upper position, such as may be effected after the completion of a blowing operation and while the hot gas, fume or eflluent from the vessel A is still discharging into the hood. A post crane apparatus B which is securely mounted or positioned on or with respect to the mill floor is provided with an outwardly-projecting, vertically-fixed jib frame F. The jib frame F supports the hood D when it is raised from its sealing-off (full-line) position I, to its upper dot-and-dash position II of FIGURE 1 by flexible cable or chain means which suspends the hood. The flexible mounting of the hood enables it to self-align with vessel A and receiver G when it is lowered into a connected relation with them. The lance E is shown suspended and raised and lowered between positions I and II of FIGURE 1 by means of a vertically-movable jib frame C of the post crane apparatus B and which carries clamping finger or closure gate means H that is adapted to open and close about the lance. Both the jib frames C and F are adapted to be swung by the post crane apparatus B, although the frame F is vertically stationary while the frame C is adapted to be raised and lowered.

Referring particularly to FIGURES l and 1A, the converter vessel or furnace A is shown provided with an inner refractory lining 11 and an outer metal (steel) shell 13. The refractory lining 11 at its upper end has a substantially annular or cylindrical inner portion 12a that extends from frusto-conical portion 12 and defines an open mouth for the vessel; it terminates in a substantially horizontal upper lip portion 12b. The outer plate wall 13 of the vessel (customarily steel plate) terminates in an annular flange structure 13a to receive and position a temperature-resistant reinforced metal annulus member 14 that, at its upper end, carries an annular sealing lip, seating rim or ring 15. The seating rim 15 is of a suitable metal such as cast iron to resist the high temperatures and provide an effective and non-sticking type of seal with the nose portion of the hood D which may be of steel; it is shown as projecting outwardly, converging upwardly, and as being of frustrum shape. I have found that it is important to avoid a steel-to-steel joint which will tend to adhere under the high temperatures involved.

Z As shown, the seating rim 15 may be sloped to provide a relatively narrow, non-sticking ring area of sealing abutment or contact' with the mouth or nose portion of the hood.

I have found that the water or cooling-fluid jacketirrg of the hood, and particularly of its nose end portion, is also important in providing and maintaining a good sealing off and interfitting cooperation with the seating lip rim 15 of the vessel A. That is, the high temperatures involved would otherwise tend to cause a distortion and burning-out of the hood members. A poor sealing action as well as a'sticking of the joint members must be avoided. However, I assure an effective moving of the hood D into and out of a full closing-off relationship with the vessel A. By the means shown, I have been able to fully inhibit the introduction of ambient atmospheric gases during the blowing operation, and after the blowing operation while efiluent continues to issue from the furnace vessel.

In FIGURE 1, I have shown an exemplary form of apparatus for controlling the operation of the hood D as well as the lance E and follow the general construction shown in my co-pending application 722,257 entitled Hood Post Crane. Although other suitable apparatus may be used, it must be emphasized that such apparatus must be of a type that will be capable of moving the hood D as a unit into and out of an effective aligned-seal ing relationship with respect to the vessel A and the receiving apparatus G, that will provide a proper manipulation of the lance E as well as the hood D, and that will permit a full single charging of the vessel with metal scrap without obstruction by the hood.

I have shown a ring gear traction member 4% having teeth 40a to mesh with a beveled drive gear 41 to effect rotation of a post crane B. In this connection, a motor 45 carried by the crane operatively drives a gear train and the shaft of the bevel gear 41, to cause rotative movement of the post crane about the member 40. An outer peripheral portion 40b of the member 40 is beveled to define a track for depending guide rollers 46 that are freely rotatable, being journaled in bearings 47 carried by the post crane frame structure 43. It will be noted that the bearing 42 for the beveled gear 41 is also carried by the frame structure 43.

The jib F has an upright member 58 that is fixed to the structure 43 and a unitary horizontally outwardly-projecting portion 58a that swing with the post crane B from full-line position I of FIGURE 2 to the dot-anddash position II. In this manner, the hood D may be swung into and out of a cooperating or aligned relationship with respect to receiving apparatus G and the vessel A, so that the vessel may be rotated and poured, again rotated, and then fully charged in accordance with best practice. There is no need to partially charge the scrap while the vessel A is in a tilted position, and then turn the vessel to a fully upright position to dump the scrap on the bottom or hearth of the vessel, and repeat such procedure until the vessel is fully charged, since jibs C and F and the hood and lance carried thereby can be fully swung out of the way.

The wall body of the hood D, see FIGURE 1, is provided with a forward pair of transversely spaced-apart support lugs 19 and a back pair of transversely spacedapart support lugs 19a. Suspension link, chains or'cables 69, and 69a are respectively connected to the lugs 19 and 19a on each side of the hood, and pass over idler sprockets or pulleys 70 and 70a that are rotatably mounted on the jib F. The chains 69 and 69a of each side of the hood are tied together by a link 68 and connected thereby to a single side chain or cable 66 length (there are a pair of side lengths) which passes over a pulley or idler sprocket 67 and is connected within a telescopic head sleeve 65 to a screw-down 64 that is mounted on the structural framework of the post crane B. A motor 63 3 drives the screw-down 64 to positively raise and lower the hood D by means of the pair of chains 66.

The raising and lowering jib C for the lance E also has a vertical member 56 and an outwardly-projecting integral horizontal portion 560:. It is raised and lowered by means of a motor 50, a winding drum 51 and a cable 52. The cable'passes over an idler pulley 53, a side guide pulley 54, and an end pulley 55 and is fixed to the structural framework at 57. Thus, winding the cable 52 on the drum 51 will effect a raising of the jib C and an unwinding will effect a lowering of it.

In FIGURE 1 of the drawings, I have shown an auxilary hoist 61 (above the jib C) which may be hooked through an eyelet 60a in a head part 60 of the lance E to raise the lance a' suficient distance to clear the furnace or vessel A when the post crane apparatus 13 is to be employed to swing the hood D, as well as the lance E, from their position I towards position II of FIGURE 2 of the drawings. The jib C may carry a pair of fluid-operated clamping fingers H (described and shown in my copending application) for cooperating with lower gate fingers in holding the lance in an aligned vertical position. It should be noted that the motors, such as 45, 50 and 63, are provided with suitable braking means, such as magnetic brakes, to assure holding a given position of the lance jib, the hood, the post crane, etc.

The Hood Construction As shown in FIGURES 3 and 4, the hook D has an inner or hot wall b of metal plate member construction and a spaced outer or cold wall a also of metal plate construction. These Walls are mounted in a spaced-apart relationship with respect to each other, as particularly shown in FIGURES 4, 7, 8 and 9, to define a fluid-cooling chamber or water-jacketing therebetween. As also illustrated particularly in FIGURES 4, 7 and 9, the open inlet mouth or nose portion of the hood is defined by a front, substantially planar plate member 16 and a lower pipe section member 16b that are joined by welds w (see FIGURES 7 and 9) at substantially planar end portions of the member 16b.

Stay bolts, pin elements or stubs 23 (see FIGURE 8) are provided at spaced locations between the outer and inner members a and b to reinforce them in their spaced relationship with respect to each other and, at the same time, to permit limited expansion and contraction of the inner members b with respect to the outer members a, but without providing what amounts to a direct or full metal-to-metal connection between them. The shank of each bolt 23 projects through an opening in the outer plate members a, as shown particularly in FIGURE 8, and is secured in position with respect thereto by a closingotf washer 24 and weld metal w. The inner end 23a of each bolt or pin 23 is threaded to receive a nut 25; thread adjustment may be effected before the washer 24 and outer end of the bolt 23 are welded in place to the wall members a. The nut 25 is welded to the inner side of the inner or hot plate members b. I have made a new discovery in this connection, namely, that the threads between the nut 25 and the thread portions 23a of the bolt, in effect, provide a somewhat indirect or poor conducting type of joint (by reason of the spacing and limited contact of the threaded portions), such that heat transfer is minimized and is of a somewhat indirect nature. I also thus provide a flexible two-part element construction.

Baffle members 26 of metal construction extend along the cooling space and are only weld-secured to project from the inner side of the outer plate member a into a spaced but close adjacency with the inner plate member b and end members, such as Md, 1612, etc. (see also FIG- URE 6). This is also highly important in preventing damage to the structure under the high temperatures involved (in the neighborhood of 3000 degrees F.).

As shown in FIGURES 3, 4 and 5, the wall plates (1 and b are shaped to provide a hood wall construction that defines a susbtantially right angular relationship between its side and bottom openings and a relatively short length and direct fluid passageway-defining enclosure. Wall portion 16 (see FIGURE 4) inclines upwardly-inwardly to define a convex inner joint with a front portion 16g of somewhat annular or collar shape that defines a feed opening wall portion for material additions to be added to the vessel A. Such feed opening wall portion has a substantially horizontal annular top flange member 20 that closes-off the inner and outer members a and b and defines a seat for a closure gate 72 (see also FIGURE of an additive funnel, chute or open-end feed wall arrangement. The back portion of the wall 16 is shown connected by bent portions to a substantially horizontal fluid-outlet defining wall 160 that terminates in a vertically-extending chill-flange seating wall or flange 16d whose surface plate wall member b forms a wiping-sealing joint with the cooperating flange portion 35 (see also FIGURE 1) of the receiver apparatus G. The top of the wall portion 160 is shown connected by a bend to a downwardlysloped top wall portion 162 which is, in turn, shown connected by bends to a collar-like wall 16 that defines a central lance opening and the collar-like fOl'WZIIdlY-POSI- tioned wall 16g that defines the additive opening wall portion.

The wall 16 of the lance opening is closed-oif by a substantially horizontal seating flange or plate member 17 that cooperates with lance gate means. As shown particularly in FIGURES 3 and 10, the flange I7 is reinforced and supplemented in its positioning action as to the lance gate means by a transversely-extending bar assembly 18.

FIGURE 9 illustrates how inlet and outlet nipples 22 and 22' (of similar construction) may be mounted with respect to the outer wall plates a of the hood. As shown in FIGURES 4 and 5, lower connector nipples 22 may be employed to introduce cooling water into the cooling chamber of the hood and upper nipples 22' may be employed to exhaust warm water therefrom toa circulating system (not shown). Additional nipples such as 22:: and 22a are provided for connections, if needed, and when not used are provided with closing-off drain plugs, see particularly FIGURE 5.

As illustrated in FIGURES 3 and 4, I provide an upper pipe connection between the two collars I61 and 16g that consists of pipe member 21, coupling 21a, and pipe member 2111. This eliminates the formation of steam and provides full fluid circulation through upper or higher points of the structure to avoid hot spots and high pressure areas that may damage the hood or its members.

In FIGURE 7, I have illustrated handholes that are provided with removable closure members 30 to facilitate cleaning out the interior of the jacketing. Each hole is provided with a sealing ring 29 that is secured to the plate member a (as by welding). The ring 29 carries a suitable ring gasket 29a of asbestos material on its back face. A clamping cover or cap member 311 is adapted to fit and seal against the gasket 29a and has an annular ring 31a to interfit with the ring 29 and align the cover in its sealing position. The cover member 31 also has a centrallyconnected outwardly-projecting bolt 3111 which receives a clamping yoke 32 and is threaded to receive a washer 33 and nut 34 to clamp the cap 31 in sealing abutment against the ring 29.

Although in FIGURES 3 to 5, inclusive, I have illustrated an exhaust hood D of unitary construction, I also contemplate the employment of a so-called multi-section or water-jacketed panel type of construction. For example, panels of 2 x 3 or 4 feet in size may be bolted to a framework and detachably secured to each other by annular sealing bands. Such panels may then have independent supply and exhaust connections for cooling water or may be interconnected in series by detachable or removable connections on the outside of the hood wall.

In FIGURE 1, I have shown a somewhat flexible type of suspension means for the hood which enables it to have a substantially self-aligning action in obtaining an effective sealing-off joint with both the sealing lip flange 15 of the vessel A and the inlet face plate or flange 35 of the receiving apparatus or spark trap G. Heretofore, many of those skilled in the art have felt that it was impractical to even attempt to provide a fully sealed-off relationship between a vessel or furnace and an associated hood. One reason is that it has been heretofore thought to be impossible to provide a good seal and one which will not stick when the hood is to be removed; another reason is that some of those skilled in the art were not convinced that a full exclusion of atmospheric air was advisable. I have not only found that it is desirable, but have been able to make it practical in a simplified manner from an operational standpoint, and without an intermediate sectioned collar. That is, I have been able to provide apparatus that will take the complete volume of fume or efliuent discharge directly from a vessel or furnace without damage to the hood and without the necessity of employing the cooling action of ambient atmospheric gases. I have found that it is desirable, rather than deleterious, to fully exclude the ambient air, since it greatly reduces the volume load and has other desirable effects.

Although I have shown a receiving, spark trap or fume processing apparatus G somewhat diagrammatically, a full exemplary final type apparatus suitable for a utilization, such as here involved, is shown in my Patent No. 2,803,450. As to the hood B, although I have not shown means internally thereof for applying a cooling fluid spray, for example of water, directly to the effluent, I have determined that such is not necessary particularly, where as here, the volume of gases is reduced and the full direct flow is directly passed through the hood in a relatively short path into the receiving apparatus G. However, spray means may be employed, if desired, see the disclosure of FIGURES 10 and 11 of my Patent No. 2,847,006.

Additive Apparatus I have found that it is desirable tosupply suitable additives to the vessel or furnace A during the refining operation and thus, during the period when the hood D is in its closing-off or sealed relationship with the vessel or furnace. Typical additive materials are lime and mill scale, which are of granular or powder-like nature such that they can be fed by means of a pipe or conduit directly through the hood into the furnace. However, the idea of employing additives while the hood is in place poses the additional problem of suitably sealing or closingoff the additive opening in the hood to avoid aspirating air therethrough and also to avoid loss of the eflluent or fume discharge through such opening into the atmosphere. In this connection, the opening is desirably in the top portion of the hood as is an opening for the lance, both of which serve to introduce processing material during the operation of the vessel. The lance opening should thus also be closed or sealed-off during the operation of the apparatus or more specifically, during the refining operation and while the effluent continues to discharge from the vessel or furnace A.

In accordance with my invention, I have provided water or cooling fluid-jacketed open feed wall portions or collar walls in the hood for both the additive and lance openings therein. These collar walls project upwardly of the hood and define jacketed sleeve or collars having upper seating faces for closure gate means.

With particular reference to the additive arrangement shown in FIGURES 10 to 13, inclusive, the upwardlyprojecting wall or collar 16g of the hood has a sealing flange face 20 that is adapted to operatively receive and cooperate with a goggle or slide gate part or member 72. The gate part 72, as shown particularly in FIG- URES 10 and 11, has an open or passageway portion 72b therethrough adjacent its one side to coincide and align with the diameter of the collar 16g and rest along its bounding area upon the sealing lip or flange 20. This position is shown by the full lines of FIGURES and 11 and is the feed position for the additive materials.

A bifurcated'support arm 73, secured to the hood wall, pivotally mounts a converging back end portion of the gate part 72 by means of a swing pin 73a (see FIGURE 10). A fluid-operatedreciprocating motor 74 is pivotally carried on the wall of the hood by a bracket or bifurcated part 75 and is alternately supplied with operating fluid (such as air) through piping 74a and 74b for reciprocation or reverse movement. The piston rod of the motor 74 is pivotally connected to a side-projecting lug or ear portion 72a of the gate 72 by a bifurcated head part 76 to actuate the gate between the additive feed position I of FIGURE 11 and a closing-off position II of the same figure. It will be noted that when the gate means 72 is swung to the left-hand dot-and-dash position of II that a closed wall portion of its body is presented to the opening above the collar 16g. Like the other parts of the hood, the gate part 72 is water-jacketed or cooled and is of a similar construction to the wall of the hood or to the lance gate means (see FIGURE 16). In FIG- URE 10, I have shown flexible cooling fluid lines 76a and 7611 connected to the gate part 72 to provide it with a full circulation between its spaced-apart inner and outer plate walls.

To guide the additive materials and provide a sealedoif relationship with a supply conduit, such as 86, I have provided a cone or funnel-shaped open-end part or feed wall or chute 81 that is securely mounted in a fixed position on the wall of the hood by a framework 80, see FIGURE 10. The conduit 86 is of goose-neck shape (see FIGURE 10A) and has a lower end portion 83 that is provided with a cone-shaped, open, plug nose end part or head 82 that is adapted to fit or seat on the inner seating surface of the funnel-shaped part 81 and define a fluid sealed-off relationship therein when additives are being introduced. The interfitting seating-sealing action of the plug nose 82 within the chute or funnel part 81 is of a self-aligning nature, due to the fact that the conduit 86 and its end portion 83 have a somewhat universal type of joint connection 84 and are swingably mounted on oppositely projecting pins 94 by flange collar 93. I have also shown position stops 90 for limiting the maximum inward or downward movement or swing of the conduit 86 and its nose plug 82.

In FIGURE 13, I have shown details of the construction of the joint 84, as well as of the nose plug 82. As disclosed, the open-end plug 82 may be weld-secured at w over the short-length pipe member or conduit portion 83 which is, in turn, weld-secured to and within an intermediate coupling body 85. The body 85 projects radially out-wardly at its upper end and has a rounded nose portion 85a of somewhat hemispherical section that is adapted to abut against and pivotally receive therein a similar, rounded or shaped nose portion 87a of a second or inner coupling body part 87. The body part 87 has an upper bore to receive the end of the conduit or pipe 86' therein and is secured thereon by weld metal w. The body part 87 also has an outwardly-projecting annular flange portion 87b which cooperates with a similar flange portion 88b of a third or outer body part 88 and which is removably secured thereto by nut and bolt assemblies 89. The third part 88 has a rounded lower surface wall portion 88a which surrounds the wall portion 85a of the part 85 and holdsit securely in position in abutment with the portion 87a of the part 87. It is thus apparent that the part 85 may be pivoted and rotated with respect to the parts 87 and 88 to provide a self-aligning, fittingsealin'g action of the plug part 82, when it is introduced into the funnel part 81.

Lance Gate Means Referring to FIGURES 14 to 18, inclusive, I have illustrated a swing gate means or apparatus for the lance E which, as shown particularly in FIGURES 15 and 17, may be employed to both guide or grip the lance E and to seal-01f the opening in the hood D through which the lance extends into the furnace or refining vessel A. Such gate means comprises a pair of gate swing fingers or parts 97 and 97, each of which is of hollow construction (see FIGURE 16). Inlet nipples, such as 98a and 98'a, supply cooling fluid through to the gate parts; warm fluid is exhausted through outlet nipple connections 98b and 9871. Like the hood wall, the wall of the gate means has outer or cold wall plate members a and inner or lower hot side plate members I) that are secured together by weld metal w at their sides or ends (see FIGURE 16). In addition I have shown stay bolts which are secured by weld means to project inwardly from the upper or outer plate members a and have externally-threaded stud portions 115a of enlarged diameter. Instead of nuts of the hood construction, I provide the inner or lower plate members 12 with integrally-projecting nubbins 114 that are internally-threaded to removably receive the threaded portions 115a. Thus, the internal connections between the plate members a and b are of the same general type as of the hood, itself, in that they are of an indirectly connected type that will inhibit or restrict transfer of heat therebetween; they also are of a flexible type.

Gate finger or part 97 (see FIGURE 14) is of somewhat U-shape in that it has finger clamping or sealing projecting portions 97a that are offset on their under face sides to interleave with portions 97a of part 97, and define a valley or depression 97!) therebetween of rounded shape corresponding to the shape or curvature of the outer circumference of the lance B (see FIGURE 17). The other gate part 97 has a pair of finger portions 97a that are oflfset from the upper face of the part 97 and that have substantially planar side edge faces that oppose the part 97. The finger portions 97'a, between them, define a depression or valley 97'b that is of substantially semi-circular shape corresponding to the outer diameter of the lance B (see FIGURE 17). Thus, as shown in FIGURE 17, when the gate parts 97 and 97 are closed with respect to each other, they have a relatively closely-interfitting rectangular-area-defining shape which substantially surrounds the lance E and slide on the flange 17 to seal-off the opening and grip the lance. It will be noted that the finger portions 97a are offset from the bottom side face of the part 97 to interleave with or overlap the finger portions 97'a when the parts 97 and 97' are in the closed position of FIGURE 17.

The swing gate parts 97 and 97' have backwardlyextending, adjacent, inner and interfitting swing arm portions 97c and 97'c that are pivotally mounted by a bearing pivot pin 100 on a cross arm or gate bar member 110, see particularly FIGURES 14 and 15. The pin 100 is shown removably held in position by a bolted-on clamping piece or keeper 104, see FIGURE 15, and has a hollow bore extending therethrough to bypass a vertically-extending pipe or gland element 125. The pipe element provides a mounting (as shown particularly in FIGURES 15, 17 and 18) for a piping gland of the cooling fluid connections, such that these connections may have non-flexible piping to the parts 97 and 97 from such pivot pin 100, although short-length flexible connections are required to it from the supply system.

The outer ends of each of the gate parts 97 and 97' have bifurcated or bracket end portions 97d and 97d that are pivotally connected by pins 101 with respect to a pneumatic or fluid-operated motor 182; the portion 97d is connected to the end of piston rod 1I2c and the portion 97d is connected to an end portion 102d of the housing of the motor 102. The motor 102 is adapted to move its piston rod 102:: in and out to swing the parts 97 and 97' between the open position of FIG- URE 14 and the closed position of FIGURE 17. Flexi- 13 ble fluid supply and exhaust lines 1021) and 1020 are provided to the motor 102 for actuating its piston in its reciprocating movement.

As shown in FIGURES 14, 15, 17 and 18, the pivot pin 100 is carried by the cross arm member 110 which also has an adjustment swing mounting at 111. It will be noted that the mounting 111 is pivoted on a fixed portion 109]) of an extending frame portion 109:: of a cross beam member 109a of the structure 109 (see FIG- URE 14) of the jib frame C of FIGUREI of the drawings to provide for self-alignment of the finger parts 97 and 97' about the lance. As shown in FIGURE 17 of the drawings, stops 112a and 11212 limit the swing adjustment of the member 110 to provide a maximum movement of about 3 inches at the lance. As a result, the closing position of the gate parts 97 and 97' will self-adjust to meet different positions of the lance E. It will be noted that the gate parts 97 and 97' have a wipingsealing action on the seating face of the flange 17, see also FIGURES and 14 of the drawings. The amount of opening of the finger parts 97 and 97 is controlled by stop ears or abutments 97e and 97'e which, as shown in FIGURE 14, in their outer positions, strike or abut against outwardly-projecting stop bars 108. The stop abutments also return the gate means to a central posit1on irrespective of any misalignment of the lance. The bars 103, as shown in FIGURES 14 and 17, are secured to project from the structure 109 of the jib frame C.

Cooling fluid may be supplied, as shown in FIGURES 15, 17 and 18, by piping 120, through connector 120a, flexible hose 121, connector 121a (that is secured to a downwardly-projecting central mounting plate 119), gland pipe 125, and supply piping 122 and 126 for the individual parts 97' and 97. Warmed cooling fluid is exhausted from the parts 97' and W through piping 123 and 127, connector 128a, piping 128, flexible hose 129 and piping 130. It will be noted that the air connections 102a and 19211 to the fluid motor 102 are of flexible construction to permit the motor housing to move when its piston rod 102a moves inwardly and outwardly to provide a free and easy opening and closing action of the gate means.

What I claim is:

1. In a furnace installation employing a refining vessel having an upwardly-open mouth, an efliuent receiving apparatus, and an exhaust hood for receiving and withstand mg hot eflluent in the neighborhood of 3000 degrees F. and higher from the mouth of the vessel and conducting the effluent to the receiving apparatus; a metal flange structure about the mouth of said vessel and having an upwardly-converging seating rim that projects outwardlydownwardly in a spaced relation with respect to the mouth of said vessel, said hood having a unitary metal wall body defining an enclosed effluent passageway therethrough, said wall body having an open inlet nose portion at one end of said passageway and constructed to removably fit over the mouth of said vessel and rest upon said seating rim to provide a sealed joint therewith, said inlet nose and said seating ring being of different materials that have an effective non-sticking type of sealing relation with each other under high temperatures to which the metal flange structure of the mouth of the vessel is subjected during the operation of the vessel, said body having an open outlet portion at the opposite end of said passageway to cooperate with said receiving apparatus and deliver effluent thereto, and means cooperating with said wall body to move said nose portion into and out of an aligned seating relation with said seating rim.

2. A furnace installation as defined in claim 1 wherein said inlet nose portion is of steel construction and said seating rim is of iron construction of frustrum shape.

3. In an exhaust hood construction for receiving and withstanding a relatively hot fluid effluent in the neighborhood of 3000 degrees F. and higher from a generator and deliver it to a receiving apparatus which comprises, a unitary hood body having an inlet portion to receive hot eflluent from the generator and having an outlet portion to deliver the hot effluent to the receiver, said body defining an enclosed passageway between said inlet and outlet portions for passing the hot efiluent therethrough, said body being of metal plate construction having an inner plate wall in a spaced-apart relationship with an outer plate wall and defining a cooling fluid passageway therebetween, said inner wall being curved along said passageway and defining a relatively smooth surface area therealong, said inner and outer plate walls being connected at said inlet and outlet portions by rounded nose portions, and heat transfer limiting dual element means carried by said outer plate wall and cooperating with said inner plate wall along the spacing therebetween to flexibly limit inward contraction and outward expansion of said inner plate wall with respect to said outer plate wall.

4. An exhaust hood construction as defined in claim 3 wherein, said rounded nose portions of said body are weld-secured to said inner and outer plate walls along substantially planar portions of said nose portions and said inner and outer plate walls.

5. In an exhaust hood structure constructed for movement into and out of a cooperating eflluent-receiving relation with the mouth of a tiltable furnace vessel and for withstanding and passing fluid effluent in the neighborhood of 3000 degrees F. and higher from the furnace mouth therethrough in a fluid-sealed-ofl relation with respect to the atmosphere into an eflluent conditioning receiver, a unitary enclosing hood wall defining an efliuentdirecting passageway therethrough and having an open bottom nose portion to cooperate with and receive effluent from the furnace mouth and having an open side portion to cooperate with and deliver eflluent from the passageway to the eflluent conditioning receiver, means for moving said hood wall as an integral unit simultaneously into and out of the above-defined cooperating relationships with the furnace mouth and the conditioning receiver, said hood wall having spaced-apart inner and outer metal shell wall portions defining a cooling-fluid-receiving chamber therebetween, expansion and contraction controlling nut and pin means threadably connected between said inner and outer shell wall portions, said shell wall portions having an upwardly-open portion defining a passageway through said wall for introducing processing material into the furnace vessel, said open portion having a surmounting sealing lip thereabout, swing gate means having portions operatively positioned for sliding-wiping movement into and out of a fluid-sealing-olf seating position with said sealing lip to open and close-off the passageway of said open portion, and said gate means having inner and outer metal shell wall portions defining a cooling-fluidreceiving chamber therebetween, so that said gate means will retain its shape and an accurate fitting relationship with said sealing lip under high temperatures to which the structure is subjected.

6. In an exhaust hood structure constructed for movement into and out of a cooperating effluent receiving relation with the mouth of a tiltable furnace vessel and for withstanding and passing eflluent in the neighborhood of 3000 degrees F. and higher from the furnace vessel therethrough in a fluid-sealed-oif relation with respect to the atmosphere into an etfiuent conditioning receiver, an enclosing hood wall of unitary construction defining an efliuent-directing-passageway therethrough and having an open bottom nose portion to cooperate with and receive efliuent from the furnace mouth and having an open side portion to cooperate with and deliver effluent from the passageway to the eflluent conditioning receiver, means for moving said hood wall as an integral unit simultaneously into and out of the above defined cooperating relationships with the furnace mouth and the conditioning receiver, said hood wall having an upwardly-open portion defining a passageway therethrough for introducing processing material into the furnace vessel, said open portion having a surmounting sealing lip thereabout, swing gate means having portions operatively positioned for slidingwiping movement into and out of a fluid-sealing-off seating position with said sealing lip to open and close off the passageway of said open portion, an additive wall part projecting upwardly from and positioned in an aligned cooperating relation with respect to said open portion to feed additive material through the passageway of said open portion when said gate means is in an open position, and said gate means having portions providing a-sealedoff relation between said additive wall part and said sealing lip with respect to the atmosphere when said gate means is in its open feed position.

7. In an exhaust hood construction for receiving and withstanding hot fluid eflluent in the neighborhood of 3000 degrees F. and higher from the mouth of a generator suchas a converter furnace and for conducting the efl luent to a receiving apparatus without contaminating the surrounding atmosphere and without aspirating air therefrom which comprises, a unitary hood body defining an enclosed efliuent passageway therethrough, said body having an inlet portion at one end of said passageway adapted to fit closely over the mouth of the generator to directly receive eflluent therefrom, said body having an outlet portion at the opposite end of said passageway adapted to closely fit with the receiving apparatus to discharge the eflluent thereto, said hood body comprising inner and outer metal wall plate members in a spaced relation and connected end plate members defining a fluid-cooling chamber, a rounded hollow end inlet nose portion to fit over the mouth of the generator and a hollow flange outlet portion to fit with the receiving apparatus; said plate members being connected by weld metal only at locations where the members are of substantially concave and planar contour, heat-transfer-minimizing dual-element means connected at spaced locations between said inner and outer plate members to limit their expansion and contraction with respect to each other, and said dual-element means having one element rigidly secured to said outer plate member and connected flexibly-threadably through its other element to said inner plate member.

8. An exhaust hood construction as defined in claim 7 wherein, baffle members are secured to said outer plate members and project across in a closely spaced and separated relation with said inner plate members to define fluid-directing paths along the cooling chamber.

9. In an exhaust hood construction for cooperating with the mouth of a furnace vessel and for withstanding and passing high temperature effluent from the vessel, a unitary hood body having an inlet portion to receive hot effluent from the vessel and having an outlet portion to deliver the hot efiluent, said body defining an enclosed passageway between said inlet and outlet portions for passing the hot eflluent thereto, said body being of metal construction and having an inner plate wall in a spaced-apart relation with an outer plate wall and defining a cooling fluid passageway therebetween; expansion-contraction controlling means for said plate wall comprising, bolt-like pins carried by said outer plate wall and having threaded end portions extending across the cooling fluid passageway towards said inner plate wall, and internally-threaded nut projections carried by an inner side of said inner plate wall to threadably-receive the threaded end portions of said pins therein.

10. In apparatus for receiving and withstanding hot eflluent in the neighborhood of 3000 F. and higher from a mouth portion of a converter vessel and for conducting an eflluent-conditioning receiving apparatus without contaminating the surrounding atmosphere and without aspirating air, wherein the receiving apparatus has an inlet portion and the vessel has a seating rim about its mouth portion that projects outwardly-downwardly in a spaced relation with respect to the mouth of the vessel, a coolingfluid-jacketed exhaust hood having an enclosing wall defining an efliuent flow passageway, said exhaust hood being of'unitary construction and having a downwardly-projecting cooling-fluid-jacketed inlet nose defining a rounded seating edge and adapted to move downwardly about the mouth portion of the vessel into a cooperating position with said seating rim to seal-off the connection between the vessel and said hood, said exhaust hood having a cooling-fluid-jacketed side outlet flange to seat with the inlet portion of the receiving apparatus and deliver eflluent thereto, said flow passageway extending upwardly from said inlet nose and sideways towards said side outlet flange to directly conduct eflluent into the receiving apparatus, means for raising and lowering said inlet nose and side outlet flange into and out of an aligned seating relation with the vessel and the receiving apparatus, a cooling-fluid-jacketed open collar portion projecting upwardly through said hood to supply additive materials to the vessel through said hood, a second cooling-fluidjacketed open collar portion projecting upwardly through said hood to pass an oxygen lance therethrough, said open collar portions having interconnecting cooling fluid lines therebetween adjacent their upper ends, and cooling-fluidjacketed swing-slide gates operatively positioned to swing and slide along said open collar portions for opening and closing them off.

11. In an exhaust hood structure constructed for movement into and out of a cooperating eflluent-receiving relation with the mouth of a tiltable furnace vessel and for withstanding and passing fluid effluent in the neighborhood of 3000 F. and higher from the furnace mouth therethrough in a fluid-sealed-oif relation with respect to the atmosphere into an effluent-conditioning receiver, a unitary enclosing hood wall defining an eflluent-directing passageway therethrough and having an open bottom nose portion to cooperate with and receive effluent from the furnace mouth and having an open side portion to cooperate with and deliver efiluent from the passageway to the eflluentconditioning receiver, means for moving said hood as an integral unit simultaneously into and out of the abovedefined cooperating relationships with the furnace mouth and the conditioning receiver, said hood wall having spaced-apart inner and outer metal shell wall portions defining a cooling-fluid-receiving chamber therebetween, said shell wall portions having an upwardly-open portion defining a passageway through said wall for introducing processing material into the furnace vessel, said open portion having a surmounting sealing lip thereabout, swing gate means having portions operatively positioned for slide-wiping movement into and out of a fluid-sealing-ofl seating position with said sealing lip to open and close-ofl? the passageway of said open portion, said gate means having inner and outer metal shell wall portions defining a cooling-fluid-receiving chamber therebetween, so that said gate means will retain its shape and an accurate fitting relation with said sealing lip under high temperatures to which the structure is subjected, expansion and contraction controlling nut and pin means threadably connected between said inner and outer shell wall portions, said nut and pin means having bolt-like pins carried by said outer shell wall portion of said hood wall and having threaded end portions extending across its chamber towards said inner shell wall portion, and having internally threaded nut projections carried on the inner surface of said inner shell wall portion to threadably-receive the threaded end portions of said pins therein.

12. In an exhaust hood structure as defined in claim 11 wherein said gate means has expansion and contraction controlling means between its said inner and outer shell wall portions of the type defined for said hood wall.

13. In an exhaust hood construction at one end cooperating with an open mouth portion of a furnace vessel for withstanding and passing fluid efiluent in the neighborhood of 3000" F. and higher therefrom which comprises,

an enclosing wall body defining an effiuent-directing passageway therethrough, an open portion in said wall body to introduce processing material through the hood into the vessel, a funnel-shaped feed wall having an outwardlydiverging open seating portion and an inner converging open-end portion in cooperating spaced alignment with said open portion; a swingably-mounted feed conduit, an open end feed plug having a pivot joint connection to an end of said feed conduit for inward self-aligning swinging movement to, in its innermost position, seat on said open seating portion and seal-off the joint therebetween; means connected to supply processing material through said feed conduit to said feed plug, along said feed wall, through said open portion and the hood into the vessel; gate means swingably positioned between said open portion and the inner converging open-end portion of said feed wall for slide-in movement therebetween to close-off said upper portion with respect to said feed wall when said feed plug is moved outwardly and for slide-out movement therebetween to open-01f said open feed portion with respect to said feed wall and maintain a sealing-off connected relation therebetween when said feed plug is moved inwardly into its seating position with respect to the open seating portion of said feed wall.

References Cited in the file of this patent UNITED STATES PATENTS 100,003 Bessemer Feb. 22, 1870 723,501 Thofehon Mar. 4, 1903 1,014,314 Marshall Jan. 9, 1912 1,314,740 Gadd Sept. 2, 1919 1,866,824 Sheridan July 12, 1932 2,726,856 Maag Dec. 13, 1955 2,781,260 Grandpierre Feb. 12, 1957 2,852,246 Janco Sept. 16, 1958 2,855,194 Konig Oct. 7, 1958 2,893,716 Smith July 7, 1959 2,902,358 Kalling et al Sept. 1, 1959 FOREIGN PATENTS 186,946 Germany July 5, 1907 9,394 Great Britain 1890 772,632 Great Britain Apr. 17, 1957 216,198 Great Britain May 20, 1924 931,597 Germany July 14, 1955 UNITED STATE S PATENT OFFICE CERTIFICATE OF CORRECTION Patent Non 8 138 648 June 23, 1964 Harry L. McFeaters It is hereby certified that error appears in the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.

In the drawing, Sheet 6 at the bottom of Fig, 14L for "IOZb" and "1020" read 102a and 102k) column 8 line 29 for "hook" read hood column 13 line 1, for "102b and 1020" read 102a and 10210 line 9, strike out "109a"; line 10, for "14'' read l7 same column l3 line 38 for "19210" read 102b Signed and sealed this 29th day of December 1964,

( SEAL) Attest:

ERNEST W. SWIDER' EDWARD J. BRENNER Attesting Officer Commissioner of Patents 

1. IN A FURNACE INSTALLATION EMPLOYING A REFINING VESSEL HAVING AN UPWARDLY-OPEN MOUTH, AN EFFLUENT RECEIVING APPARATUS, AND AN EXHAUST HOOD FOR RECEIVING AND WITHSTANDING HOT EFFFLUENT IN THE NEIGHBORHHOD OF 3000 DEGREES F. AND HIGHER FROM THE MOUTH OF THE VESSEL AND CONDUCTING THE EFFLUENT TO THE RECEIVING APPARATUS; A METAL FLANGE STRUCTURE ABOUT THE MOUTH OF SAID VESSEL AND HAVING AN UPWARDLY-CONVERGING SEATING RIM THAT PROJECTS OUTWARDLYDOWNWARDLY IN A SPACED RELATION WITH RESPECT TO THE MOUTH OF SAID VESSEL, SAID HOOD HAVING A UNITARY METAL WALL BODY DEFINING AN ENCLOSED EFFLUENT PASSAGEWY THERETHROUGH, SAID WALL BODY HAVING AN OPEN INLET NOSE PORTION AT ONE END OF SAID PASSAGEWAY AND CONTRUCTED TO REMOVABLY FIT OVER THE MOUTH OF SAID VESSEL AND REST UPON SAID SEATING RIM TO PROVIDE A SEALED JOINT THEREWITH, SAID INLET NOSE AND SAID SEATING RING BEING OF DIFFERENT MATERIALS THAT HAVE AN EFFECTIVE NON-STICKING TYPE OF SEALING RELATION WITH EACH OTHER UNDER HIGH TEMPERATURES TO WHICH THE METAL FLANGE STRUCTURE OF THE MOUTH OF THE VESSEL IS SUBJECTED DURING THE OPERATION OF THE VESSEL, SAID BODY HAVING AN OPEN OUTLET PORTION AT THE OPPOSITE END OF SAID PASSAGEWAY TO COOPERATE WITH SAID RECEIVING APPARATUS AND DELIVER EFFLUENT THERETO, AND MEANS COOPERATING WITH SAID WALL BODY TO MOVE SAID NOSE PORTION INTO AND OUT OF AN ALIGNED SEATING RELATION WITH SAID SEATING RIM. 